hgmerge.py in mainstream mercurial distribution

[Jonathan S. Shapiro]

I don't have an opinion on the python merge script per se, but our
experience with teaching our clients how to use mercurial may be
relevant here.

In brief: the less customization that needs to be done in order for a
mercurial install to "just work" -- even if it must do so with less than
optimal performance -- the better.

For UNIX, we can mostly say to our clients "run this one command, then
you can use hg". For windows things are more complicated. There are
performance issues with cygwin, but more importantly it violates the
"too many steps" impediment. Ideally, we would like to be able to point
our Windows-based customers to a single installable "package" that will
either include all dependencies or resolve the dependency requirements
automatically (latter preferred).

All that being said, the "right thing" for the python merge utility
isn't to stick it in extras. The right thing is to (1) get the python
merge utility packaged for python-style install, (2) set up hg to add
the python merge utility's install directory to the set of search paths
for hg extensions, and (3) add the necessary support in hg so that the
set of search paths can be extended by the system-wide hgrc.

I realize that I am re-opening an issue that I had promised to fix (the
search path thing), and I apologize for dropping the ball on that. The
reason I'm popping up on this topic is simply to remind everyone that
this issue comes up pretty often, and a generalized solution may be
called for.

shap